You should probably not use the word speed and camera phones in the same
sentence without also using the word not in said sentence. =)

I use a K750i and I must say that as a point and shoot it does fill its
purpose. If you can stand still long enough and have good light, it takes
quite usable snapshots. Obviously outdoors and during the day is the best
time, but it has a help lamp that tries to make up for the lack of
flashlight, and does, at least if your subject is really close, say at one
meter or so. Going back to the speed issue; The k750i is not a fix focus
camera, so it takes what feels like ages for it to focus and take the
image. You will get somewhere between one and several seconds of shutter
delay on this device. So make sure your subject sits tight. =)

The result is fairly ok anyway. You can't compare it with the output of
a real camera, but the 2Mp makes it good enough for snapshots. I have
even printed some images and though not perfect, the paper copies where
good enough to use as post cards and to show to my friends.

Usabilitywise I actually think the camera part of the K750 is a treat!
Even when the phone key board otherwise is locked, as soon as you open
the lens cover, the phone goes into the camera application, and is ready
to shoot. So you never need to flick through loads of menues, or
remember what obscure key combination unlocked the phone, before you
can take that snapshot. Likewise, when you're done, close the lens
cover, and the phone is locked again. Also, you can adjust the white
balance using the joystick while composing your image, also convenient.

When you connect the phone to a computer with usb it is presented as a
usb disc, so even my Linux boxes recognises it automaticly as a drive.

To sum it up, it isn't a real camera. But it is usable for snapshots. Try
one out, and especially check if you can live with the somewhat sluggish
shutter delay. Other than that I dont really have any issue with it.